1. Field of the Invention
The present invention relates to an image forming apparatus for forming an image for printing print data and specific information.
2. Description of the Related Art
Specific information, such as a pre-designated fixed character string and fixed drawing (hereinafter “water mark”), has been simply overlapped with the print image on each page for printing.
In a conventional image forming apparatus, a document or any other data is created by an application using a host apparatus, such as a personal computer. A graphic image function of the created document is converted to an output suitable for an output device by a graphic device interface. A printer driver generates print data suitable for the output device and transmits the generated output data to an output apparatus (a printing apparatus). When the water mark is required to be printed on a print medium, the water mark stored in the printing apparatus is overlapped with the print data transmitted by the print driver for printing.
In the conventional image forming apparatus, however, when a plurality of pages are reduced to one sheet for printing, each reduced water mark is printed on each reduced page. Therefore, the water mark is printed in fine characters and it becomes difficult to distinguish the water mark.
Primarily, the water mark has a function of watermark. However, in the above method of overlapping the water mark with the print data, the primary function of the watermark, wherein an image is visible through light, cannot be achieved.
Also, when several kinds of documents are printed by a network printer commonly used by a plurality of users, it has been necessary for a user to set his/her own water mark every time of printing in order to efficiently take out his/her own document by the water mark. However, it has been very time-consuming and burdensome work for the user.
In addition, in case of the face-down printing, in which the print medium is output up side down, even if the water mark is printed to identify his/her own document easily, since the water mark is printed on the front face, the print medium is required to be turned over to the front face one by one.